There are millions of patients who have life-threating lung conditions for which there are potential pharmacologic therapies. Some examples of these diseases are lung cancer (primary), secondary lung cancer (metastases to the lung), pulmonary hypertension, Adult Respiratory Distress Syndrome (“ARDS”), asthma, lung organ rejection, and others. Unfortunately, such pharmacologic remedies are tolerated poorly by the ill patients who have these conditions because the drugs are toxic, potent, and delivered to the entire body rather than the lung organ where most of the pathology resides. There is an ongoing need for a minimally invasive system to control lung circulation for targeting drug delivery.
The promise of selectively delivered chemotherapy has long been recognized. This approach has been used most notably in isolated limb perfusion for melanoma and sarcoma as well as hepatic perfusion for unresectable liver tumors and metastases from colorectal cancer. In adopting this technology for the effective treatment of pulmonary tumors, similar techniques have been explored using isolated lung perfusion. These techniques require thoracotomy incisions for cannulation of delicate pulmonary vessels or risked toxic chemotherapy leakage into the systemic circulation.
In particular, while regional chemotherapy has been established as an effective means to target therapeutic agents, complexities in the lung circulation and the need for large incisions have limited its use in the chest. While catheters have been designed for placement through the heart and into the pulmonary artery (such as the Swan-Ganz catheter, which has been used for over 40 years), the balloons on these devices are too small to completely occlude the main pulmonary artery. Larger versions of such catheters exist that can occlude the main branch pulmonary artery. Unfortunately, such larger versions do not both reliably occlude the main pulmonary artery and provide predictable drainage and infusion access to all the branch vessels. This is because the branch vessels are short and variable in their conformations (see, for example, FIGS. 21A and 21B).
Attempts to develop systems for selective control of variable branches for windpipes have been made, such as by the use of a double lumen endotracheal tube design, but such devices have not been applied for vascular control, nor have they been suggested for administration of an agent for disease prophylaxis and/or therapy. Current balloon catheters tend to be unstable when positioned in the right or left main pulmonary artery because these arteries continue for very short distances before branching. Thus, they either dislodge from their intended position. If positioned deeper in the vessel, they migrate past important branches and miss large portions of the targeted organ. Accordingly, the present invention provides an improved catheter and systems and methods for use in prophylaxis and/or therapy of disease.